The present invention relates to an arrangement for an optomechanical deflector, which can be worn close to the eye(s), for a line display unit, where the deflector comprises ocular and objective functions and also a component or components for sweep generation and image turning.
It is previously known to use a deflector function in connection with a single-line or multi-line display unit where the purpose of the deflector function is to deflect radiation falling on the eye as the line-scanning function is performed on the display unit. Reference is made to European Patent Application 518834 A2, through which an arrangement with a display unit and a deflector of this type is previously known.
In the known arrangement, the sweep generation function is brought about by means of a tilting mirror which must tilt with great frequency in advanced systems. This requirement conflicts with requirements for the field of vision to be large in most cases and for the tilting mirror, for various reasons, to be positioned at a relatively great distance in front of the eye. A greater distance in front of the eye entails a need for a larger tilting mirror. The need for a relatively great distance may result from the wearer/observer having to be able to wear (conventional) glasses, from it being undesirable for safety reasons to have a rapidly tilting component very close to the eye, etc.
The components performing the four main functions (ocular, objective, image turning and sweep generation) are themselves to be capable of comprising a number of optical elements, and an optical element involved may alternatively perform more than one of said main functions. The invention is also based on the awareness that a component which is tilted with great frequency is to be small and light. Simple adjustment possibilities of the components in production are also desirable.
The main object of the present invention is to solve inter alia the problems indicated above.
An arrangement according to the invention can be considered to be characterized mainly in that one or more first tiltably arranged components performing the sweep generation can be positioned so that they are displaced from the immediate vicinity of the eye(s) in front of the eye(s) in the upward direction, the downward direction and/or towards the side, and in that each respective first component interacts with a rigidly arranged second component for the purpose of ray guidance. Further features are that the respective first or second component(s) reflect(s), by means of an associated first mirror surface or associated first mirror surfaces, incoming radiation from the line display unit to an associated second mirror surface or associated second mirror surfaces on the second or, respectively, the first component, in that the respective first or second mirror surface is cylindrical, and in that the second mirror surface(s) in turn reflect(s) radiation towards a third mirror surface or third mirror surfaces forming part of the ocular function, which reproduce(s) the respective first mirror surface for the pupil of the respective eye.
In an embodiment of the invention, each respective sweep-generating component consists of a tilting mirror of small dimensions or small mass and, in spite of this, a field of vision is established for the eye or eyes, which is relatively large by virtue of the fact that the tilting mirror is optically reproduced in the pupil of the respective eye. Furthermore, the sweep-generating component(s) or the tilting mirror(s) can be positioned in the space situated in front of the forehead of the wearer or the observer. The second mirror surface(s) then angle(s) the incoming light ray from the line display unit in towards the eye or eyes. The reproducing optics are of cylindrical shape with the cylinder axis parallel to the line display. It is also proposed that the objective function be arranged at a distance from the ocular function, which results in the optical system obtained being afocal. In a preferred embodiment, the ocular function comprises a concavo-convex cylindrical lens which is mirror-coated on the convex side, on which said third mirror surface or mirror surfaces is or are arranged. The sweep-generating component or tilting mirror can also function as an image turner or form part of the image turning function in a manner known per se. In an alternative embodiment, the ocular function can comprise one or more cylindrical lenses and a plane mirror or plane mirrors arranged close to the latter. In a further alternative embodiment, the objective function comprises one or more cylindrical lenses at the same time as the second cylindrical mirror surface(s) is (are) in the form of a field lens or concave mirror. It is also possible to have a partly transparent mirror form part of the ocular function in order to make it possible for the wearer to observe the surroundings together with the image generated in or on the retina(s) of the eye(s) by the line display unit.
By means of the above proposals, a large field of vision can be preserved in spite of the small size of the sweep-generating component which can moreover be positioned at a safe distance to the side of and/or above the eye or eyes. The observer can wear glasses. Said function can be achieved using elements known per se and the observer can observe not only the image produced by the line display unit but also, if desired, the surroundings. The new arrangement is also based on the awareness that the reproducing optics can advantageously be made cylindrical and with a small and light tilting component.